Endless Sphere

If you want to use a 1.7KWh battery with a 20KW motor, you will have to take into account discharge rates. I havent' looked at the specs of the cells you mentionned, but I'd be surprised if they can handle that much for long. You have to take that into account in your decision, it's possible to do a...

Amazing build, great pictures, awesome video....
Please post more!

Nice upgrades. Now time to get a more powerful controller. Make sure your battery can handle that though.

That being said, it's a real pain to read with all that punctuation. I bet your keyboard "." key must be pretty worn out.

Yeah a ratchet strap is even better if you have one around. Basically anything that can compress the tire circumference and hold the tire tight to the rim would work. I never managed to make the starter fluid technique work either. Every time I tried it ended up in a slow burning fire and me panicki...

I've used this technique a few times and it works very well. Much easier than the traditional method. Haven't thought of the plank with a hole trick, might make things a bit easier I should try it next time. An other useful trick to know: Sometimes it can be hard to inflate the tire the first time. ...

Is there any specific reason why you'd like to use a dual motor setup?

If not, maybe you can have a look at what the awesome/insane Youtuber Colin Furze just did:
https://www.youtube.com/watch?v=otlR05QZRrU

First of all, kudos on that casing, it is really insane! Great work, super clean. Love the way you made the mold. I was thinking in covering my Moped fairings in real carbon fiber (currently using carbon fiber Vinyl), you think it could be done? Yes, it's not very difficult but it's very time consum...

I have one more question. I decided to make a 72 volt system (24 cells Lifepo4), but my motor has not hall sensors. That's weird, I haven't seen any of those motors not having sensors. Are you really sure? Can you check again if they are not coming out somewhere from the motor axle? If your motor r...

some progress. I'm thinking of installing foam between the cells. Do I need it? I would not. It would make the battery bigger, limit the thermal transferts and also allow the cells to expand and puff, which is something you don't want them to do. What I've seen on most pouch packs I've opened was t...

Hey Everyone. I'm new here but I was hoping to get some help with Identifying and possibly getting information on a this scooter. From what I've seen it's called Raven but other than that nothing else. I've searched high and low for anything on it but it seems everything just leads to a dead end. M...

Actually the quality of my Zoom electric scooter is pretty good coz they are assembled in Calfornia actually. Looks the same as the chinese ones on the pics. The assembly is fairly good in China too, it's the hardware itself that's basic. Just look at the front fork, the rear swingarm and the wheel...

Just bought a Zoom electric scooter or moped from their California plant for about $1900. I have been trying to find an affordable and solid scooter for my commute to work and get around the city... went to test drive it in Orange County and liked it. WeChat Image_20190507185847.jpg Pros: incredibl...

3DRoboGuy wrote: ↑

May 06 2019 5:36am

Anyways, in frustration and wishing to 'get on', I ordered a 3Kw Kunray BLDC motor/controller unit over the weekend. I hope I won't live to regret my inclusiveness!!

That seems way underpowered to me!
50A controllers is barely what they put here on lightweight granny scooters.

Hi, First time on the forum, so introductions first : Does this sound feasible ? Any ideas / advice / thoughts ? Sounds like a sweet project. But you said that you are living in France. And as far as I know, regulations are pretty harsh for DIY vehicles there. I think that might be the biggest diff...

Well as it turned out the battery had no problem at all, it was just discharged a bit too much. I first took the BMS off and opened the battery to get readings directly from each tab. They were all pretty consistent (3.28V) except for one group which was quite a bit lower than the other ones (2.7V)....

Ok, give me enough time for it to sink in -- 500x245x160mm ~= 42x16x25 cm, it is the same pack you're talking about. And you're right, $1k shipped for a 72V 40Ah seems like quite a good deal, especially when it can deliver around 120 A continuous. Compared to the same price for a 48V 30Ah battery w...

I'm new to this, so hopefully someone can chime in as to whether this is obvious or not. If I get the A123 pack off ebay, it doesn't have a BMS. So I would need to get a BMS myself and add it -- several places in the forum the ANT bluetooth BMS (especially 300A version) is recommended, which I thin...

ok... that simplifies it a lot... there is no circuit breaker on the circuit... but that's not a biggie... i see that the charger port is pretty much wired into the main hot and negative... and that they all go into the speed controller together... i'm going to give this a try... and if i don't get...

Thank you Dui, May I know how can you assumed it is 300A peak? Well that's kind of an "educated guess", I cannot know for sure because Kelly controllers almost never mentions those figures. But that's about what I've seen on most controllers I tried, usually the phase currents max ratings are about...

To test without removing coatings, then make sure your probes are very sharp and pointy. Use a bit of heatshrink or insulation stripped from wires, etc., to cover the entire probe tip all teh way to the point, but not beyond it. Push the tip into the coating till it reaches the soldered pad. Even i...

to supply 280A in 72V (20KWh) if I am using Samsung INR21700-50E at 4,900mAh 10C (thx to Lefflex) https://batteryservice.bg/wp-content/uploads/2018/12/INR21700-50E.pdf the pack would be 20S 62P 72V 279Ah 1.240 cells x 69gr = 86Kg (85.560gr) I don't really understand how you calculated those values,...

I haven't measured all the cells individually yet, because, as you can see, they are pretty hard to access to. Not really--all the cells are accessible via the BMS balancing/sense wires (and the main + - pack wires for the end cells, if there arent' separate sense wires for that). Yep, That's what ...

Thanks for your inputs folks, I'll try to explain a bit better the situation: My scooter battery is divided into two paralleled batteries: the first one is a 72V 30Ah (24s3P), the second one is a 72V 20Ah (24S 2P). Each having its own BMS. Here is how the first one looks like inside: The BMS: IMG_59...

Very interesting build, this gearbox setup is sweet. I just worry about the way you attached your sprocket, I don't think this will last. At some point the bolts will probably just snap. If you can, you should probably try to machine a thick round plate with holes, instead of those spacers, that wil...

Thanks for all the feedback I’ve received which I’ve taken onboard and changed my controller and also revised the batter pack spec. I’m sticking with the QSMotor 4000w v3 but switching the controller to a Sabvoton SVMC72150 / 150A battery amps with TFT display and bluetooth (the issue I missed on t...